Insurer AmTrust has a key earnings call on Thursday. Can it persuade investors its profits result from smart management, and not aggressive accounting? Watch the stock.

The success of AmTrust Financial Services crowns the American dream of Michael and George Karfunkel. Emigrating from Hungary after the 1956 revolution, the brothers made themselves billionaires over the next half century. They built America's largest independent stock transfer agency, assembled a real-estate empire, and invested with Wall Street's high rollers and hedge funds. In 2006, the Karfunkels began bringing public their skein of insurance companies: first AmTrust, then Maiden Holdings, and, in a few weeks, National...